蹬空条件提高回采上限开采设计与工程应用

为延长矿井服务年限,多回收煤炭资源,部分煤矿进行了卸压开采后(蹬空)提高回采上限开采。针对蹬空提高回采上限开采过程中工作面设计、矿压控制、安全开采等方面存在的问题,结合张集矿8煤和11煤开采地质和工程条件,采用理论计算和FLAC3D数值模拟试验,获得了蹬空与非蹬空开采覆岩运移和支承压力特征,揭示了二次开采采动应力演化机理。基于11煤1724(1)工作面蹬空及提高回采上限开采的可行性评估分析,提出并实施了提高回采上限开采技术方案。工程应用表明:蹬空条件提高回采上限开采是可行的,为类似条件工作面开采设计提供了参考。

Mining Design in Increasing Extraction Upper Limit with Ascending Mining and Engineering Application

In order to prolong service life of coal mine and recover coal resources,increasing upper mining limit has been used after stress-relief mining at some coal mined mines,named as mining above hollow.In view of conditions for mining above hollow and problems for designing,pressure controlling,safe mining in increased upper mining limit,according to geological and technological conditions of No.8 and No.11 coal seams at Zhangji coal mine,mechanical characteristics of surrounding rock had been analyzed in combination with theoretical calculation and FLAC3D numerical simulation.Development patterns of overlying strata movement and abutment pressure were comparatively investigated and obtained between mining above hollow and non hollow.The evolution mechanism of mining induced stress was revealed after being mined.Based on mining feasibility evaluation analysis in No.11 seam mining with increasing upper limit above hollow,technology schemes for panel 1724(1) were proposed and implemented.Engineering applications show that increasing upper extraction limit is feasible in ascending mining.It provides a reference for the mining design in similar conditions.